The AC-PC line is a reference line that runs through the Anterior commissure (AC) and Posterior commissure (PC).
Application
The AC-PC line is used particularly in neuroradiology and is frequently used as a reference for axial plane orientation in MRI. The AC-PC line is also used in functional neurosurgery, which has historical reasons, as earlier neuroanatomical atlases used the AC-PC line for plane orientation.
Definition according to Talairach
According to the definition by Talairach[^1], the AC-PC line runs through the superior border of the anterior commissure and the inferior border of the posterior commissure.
Definition according to Schaltenbrand
According to the definition by Schaltenbrand[^2], the AC-PC line runs through the midpoint of the anterior and posterior commissures, allowing both commissures to be visualized on a thin axial MRI slice.
Difference
The Talairach and Schaltenbrand definitions differ by 5.81° ± 1.07°[^3].
